A turbomachine compressor has at least one stator stage comprising two coaxial shrouds extending one inside the other with substantially radial vanes extending between them, which vanes are connected at their radial ends to the shrouds.
The outer shroud of a stator stage has radial orifices in which the radially outer ends of the vanes are engaged and fastened, generally by welding. The inner shroud of the stator stage has radial orifices in which the radially inner ends of the vanes are engaged with clearance.
In the prior art, the clearance between the inner ends of the vanes and the edges of the orifices in the inner shroud is occupied by a silicone-based polymerizable sealing resin that serves to provide mechanical connection between the vanes and the inner shroud. The resin is injected directly onto the inner ends of the vanes, over a thickness in the radial direction that is relatively large (a few millimeters) in order to embed the ends. The resin is relatively flexible and presents viscoelastic behavior, thereby enabling it to accommodate both positioning tolerances of the parts and relative movements due to thermal expansion in operation, while damping vibration and providing sealing at the inner ends of the vanes.
Nevertheless, that resin does not withstand temperatures higher than 250° C., and therefore cannot be used in a compressor for which the operating temperatures exceed 300° C. At present, there is no available resin or elastomer that is injectable onto the parts over a relatively large thickness and that withstands temperatures higher than 300° C.